#include<stdio.h>
#include<math.h>

int main()
{
	int n, m;
	scanf("%d%d", &n, &m);
	int b[2000],c[2000],i,x=0;
	double average,a[2000],t,sum=0;
	for (i = 0; i < n; i++)
	{
		scanf("%lf", &a[i]);
		b[i] = m + i;
		sum += a[i];
	}
	average = sum / n;
	printf("%.1lf\n", average);
	t=fabs(a[0]-average);
	for (i = 1; i < n; i++)
	if (t>fabs(a[i] - average))
		t =fabs(a[i] - average);
	for (i = 0; i < n; i++)
		if (t == fabs(a[i] - average))
		{
			c[x] = i;
			x++;
		}
	for (i = 0; i < x; i++)
		printf("%d\n", b[c[i]]);
	return 0;
}
